• September 08, 2022 7 min read

    How Much Does A Bag Of Water Softener Salt Cost?

    salt for water softener
    So you’ve recently purchased a water softener (or are considering a purchase) and are wondering about the ongoing expenses associated with water softening? After the initial water softener system purchase, there will be two main expenses to properly maintain your system:
    1. Salt (consumable)
    2. Servicing of the Unit

    Salt: How Much Salt Will You Need to Purchase?

    First of all, ion exchange softeners require salt (sodium chloride or potassium chloride) pellets in order to soften the hard water coming into your home. This salt is held in a “brine tank” which sits next to (and is connected to) your water softener.

    A 40-lb. bag of sodium or potassium chloride will cost between $5 and $25 dollars, subject to the brand, salt purity rate, and location of purchase.

    At WaterTech, we recommend using either potassium chloride or evaporated water softener salt pellets with a purity rate of 99.5 percent. For more information on what type of salt to buy, we’ve addressed that in another blog post.

    If you find you’re going through more than one bag of salt each month, you may want to have your water specialist check your softener’s regeneration schedule. The control valve on many softeners and conditioners will automatically do the calculations for you regarding when to regenerate, but you’ll want to keep an eye on the salt level in the brine tank and add additional salt as it is consumed. You should never see standing water above the salt pellets in the brine tank. If you do, add more salt to the brine tank.

    Many purchase three (3) 40-lb bags (120 pounds total) at one time so they only have to add salt about once every three months.


    Homedepot: $5.97 for 40lbs

    Amazon: $28.95 for 50lbs

    Walmart: $4.94 - $5.96 for 40lbs

    Lowes: $4.97 - $6.49 for 40 lbs

    Acehardware: $6.49 - $9.99

    How many bags of salt do I need for a water softener?

    Be selective with your salt choice

    There are three basic types of water softener salt: rock, solar and evaporated. Rock salt, the least expensive, contains higher levels of insoluble minerals or impurities. Over time, this can result in a muddy tank, decreasing the softening efficiency while leaving impurities in your water. Solar salt, which is much more soluble than rock salt, is obtained by the evaporation of seawater and is found in both pellet and crystal form. The best option is evaporated salt, which is obtained through a combination of mining and evaporation. This is the purest form of salt at 99.99% sodium chloride.

    In general, look for higher purity salts, which will leave less storage tank residue, lowering the likelihood of salt bridges and salt mushing, and will result in less maintenance. High-quality salts—and salts in pellet form—help eliminate bridging problems. Additionally, many leading brands also offer salt products that address specific issues, such as high iron concentration, rust stains and sodium alternatives.

    What is the best type of salt to use in your water softener?

    Refilling the salt in your salt-based water softener is a major part of its ongoing maintenance. These particular systems use a brine solution to wash away the hardness minerals and regenerate the sodium-charged resin beads – which are essential to the water softening process.

    If you notice that the salt in your brine tank is running low, you’ll need to refill it as soon as possible. You will likely come across common types of water softener salts like crystals, salt pellets, and potassium chloride. But which one do you choose? Salt pellets or potassium chloride pellets? Solar or evaporated salt pellets?

    To answer those questions, let’s look at each type of water softener salt and what situation each works best in.

    Softener Salt or Softener Potassium Chloride: How Are They Different?

    Ideally, water softeners work best with salts that are specially designed for softening water. That means no dicing, table salts or any salt of that kind.

    Usually, when you want to change the salt in your water softener, you can choose from either sodium chloride (crystals, pellets and block salt) or potassium chloride.

    The type of salt you use can affect the efficiency of your water softener and the regeneration process. It can also impact the amount of sodium that gets into your softened water, the cost of salt changes, and how often your brink tank needs to be cleaned.

    Salt pellets, crystals and block salt are the three different forms of sodium chloride. Apart from being readily available in a variety of forms, sodium chloride is widely used because of its lower cost and effectiveness.

    1. pellets
    2. crystal
    3. block salt

    Salt pellets are the most common and are generally less expensive than potassium pellets. Here is a breakdown of the available options:

    • Evaporated salt pellets have the highest purity rate of the aforementioned salts and are generally the most expensive. The higher the purity of your salt (we prefer 99.9% pure salt), the less water-insoluble matter, which means less chance of “bridging”, “mushing”, or insoluble buildup in the bottom of the tank that will need to be cleaned out later.

    Evaporated Salt Pellets (Our Top Pick): Evaporated salt is the purest form of sodium-based salts for softening water. And as you’d expect, it’s the most expensive type listed here. This type of salt forms when raw salt is converted to sodium chloride and all the moisture has been removed. What’s left from this process is 100% pure salt. Because of this pure state, evaporated salt pellets are highly effective at treating hard water and making it soft. 


    • Solar salt pellets is most commonly sold in the crystal or pellet form and is made through evaporating sea water. Solar salt is more soluble than rock salt, but may not work as well as evaporated salt when your water hardness level is very high. Many solar salt brands contain 99.6 pure salt.

    Solar salt: Solar salt (more commonly known as ‘sea salt’) is a byproduct of evaporated seawater. It is naturally produced when the sun dries out the highly saline seawater. This type of salt is 99.6% pure. Also, it is highly soluble, even more than rock salt. That means it is able to dissolve much faster than other types of water softener salts. You can use it if your system suffers from frequent salt buildups, “mushing”, or “bridging”. Using this type of salt can help extend the life of your softener and lower the need for frequent maintenance.

    • Rock salt resembles small rocks or pebbles. Although this form of salt is more economical, we don’t recommend using as it contains a high amount of calcium sulfate which means it won’t dissolve well in water and can cause maintenance headaches.

    Rock Salt: As the name suggests, rock salt resembles small rocks or pebbles. It is mined underground and forms when salt deposits accumulate. Rock salt is the rawest kind of salt on this list, which means that the salt crystals from the salt itself may contain other traces. Even though rock salt is more economical, it has a high amount of calcium sulfate, so it may not dissolve well in water and may lead to constant maintenance headaches. Literally.

    • Block salt should not be used unless your WaterTech dealer recommends and raises the water level in the brine tank to ensure the blocks are fully submerged for maximum brine formation. 

    Like most things, it’s best to spend a little more up front for high quality. Purchasing bags of high-quality evaporated salt pellets will mean fewer cleaning and maintenance issues and will also help you achieve better results with your water conditioner.

    • Block Salt: Block salt is on the list of salts that are not ideal for water softeners. Some companies add a bonding agent to the salt to form the blocks, which is just more impurities being added to the salt. Therefore, we do not recommend using it.

    Potassium Chloride

    Potassium chloride is a great alternative to salt (sodium chloride), especially since it is 99.9% sodium-free. While this makes it perfect for those who are looking to reduce their sodium intake, the potassium is not healthy for people with hypertension or a history of this condition in their family. Also, potassium chloride pellets are usually more expensive and are not as accessible as salt pellets. 

    If you are thinking about switching from salt to potassium chloride pellets, you might have to increase the salt dosage program setting on the valve by about 10% to make sure that the system regenerates properly.

    How long does a 40 lb bag of water softer last?

    How much salt you’ll need to purchase and add each month will depend on the level of “hardness” in your water and the quantity of water your household consumes. Industry standard is that the average family of four with typical water hardness (roughly 7-10 grains per gallon hardness level) will use about 9 to 10 pounds of salt each week or one 40-lb bag of salt each month.

    1. Regularly check the salt level in your brine tank (at least every month). Once the salt in the brine tank falls below one-quarter full, you run the risk of not having softened/conditioned water.
    2. For optimal efficiency, keep the salt in the brine tank at least three or four inches above the water level, but no more than four inches below the top of the tank.
    3. Loosen any encrusted salt around the brine tank and ensure that the large blocks are broken up before added any new salt to it. Adding hot water to the salt blocks will help break them up.


    Is it worth it?

    In the world of appliances, water softeners are wonderfully low-key. With the exception of initially entering your water hardness level, any regeneration timing parameters and refilling the salt, they just hum along and do their job. Although low-maintenance, there are a few easy ways you can make them work more efficiently and last longer.

    Good maintenance involves refilling the brine tank with the right type of salt. Water softeners work well with sodium chloride or potassium chloride, but depending on your situation, you can use this guide to determine the type that is best for you.